Nonsintered nickel electrode

Abstract

A nonsintered NiOOH electrode for an alkaline battery including a plastic-bonded NiOOH active mass pressed onto a metallic substrate which has been previously coated with a layer of nickel dendrites to enhance the surface area of the substrate and promote adhesion of the active mass to the substrate.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. In an alkaline battery including a nonsintered nickel electrode of the type comprising an electrochemically active mass pressed onto a metallic substrate wherein said mass comprises principally nickel hydroxide, inert conductive particles having a diameter of less than about 10 microns distributed throughout said nickel hydroxide and a plastic binder for binding said hydroxide and said particles together, the improvement comprising: a strongly adherent nickel electrodeposit on the surface of said substrate, said electrodeposit comprising a sufficient quantity of nickel dendrites extending into said mass between said particles as to at least double the effective surface area of said substrate in contact with said mass and so engage said mass as to anchor said mass against premature separation from said substrate while in use.   
     
     
       2. In an alkaline battery including a nonsintered nickel electrode of the type comprising an electrochemically active mass pressed onto a metallic substrate wherein said mass comprises principally nickel hydroxide, inert conductive particles having a diameter of less than about 10 microns distributed throughout said nickel hydroxide and a plastic binder for binding said hydroxide and said particles together, the improvement comprising: a nickel electrodeposit on the surface of said substrate, said electrodeposit comprising a plurality of nickel dendrites strongly adherent to said surface and extending into said mass, said dendrites having (1) an aspect ratio of about 2 to about 10, (2) a population over said surface of at least about 10 4  /cm 2  but less than about 10 7  /cm 2 , (3) an interdendrite spacing greater than said average particle diameter, and (4) an effective surface area in contact with said active mass which is at least twice said substrate surface.